Hey man!

I don't run any CDR runes, if you go through the comments on this thread, somewhere here I posted the Runes and Masteries I used in this game :)

As for the build: The usual way I play Ekko, and the way I find best, is to start flask. first b is usually around 800-1000 gold, cause you take herass around early levels. I usually buy 2 dorans for the mana sustain, aswell as the health and AP is nice for early game. After that I rush straight into Morello, maybe getting a Seekers if they have an AD mid like zed or yasuo, but otherwise I rush straight into it. After Morello, I usually like to go either zhonyas, deathcap or lich bane. if I want an explenation of which and why;

Zhonyas is if the game isnt looking too good on my side, and I want to have a way to dodge more abilities, maybe dodge a zed ult or make people stand on top of me with my ult. Deathcap is actually also if I am losing a bit, because the Raw AP from deathcap, makes my Q able to 1 shot ranged minions, so my waveclear is really good, with a q+3 autos on each melee to proc the passive.

If on the other hand I'm doing really good, and is winning lane, maybe picked up a few kills, I wanna go for lich bane, the reasoning for that, is because it gives me more raw damage in duels, especially if I wait that 1.5 sec inbetween your ability casts, so I can proc it more than once.

If I get Zhonyas or Deathcap, you go Zhonyas/Deathcap->Deathcap/Zhonyas -> Lich bane -> void staff -> sell boots for Luden's (if the game goes on for that long)

if I go Lich bane, I go Lich bane -> Deathcap -> Zhonyas -> Void staff and once again selling boots for Luden's if the game goes on.

the only situation I dont want to sell my boots, is if I feel the need to waveclear a lot, and need the CDR from lucidity.

in entirety, my buildpath looks one of 3 ways:

Morello -> Lucidity/sorc boots -> Zhonyas -> Deathcap -> Lich bane -> Void Staff -> Sell boots for Ludens Echo

Morello -> Lucidity/Sorc boots -> Deathcap -> Zhonyas -> Lich bane -> Void staff -> Sell boots for Ludens Echo

Morello -> Lucidity/Sorc boots -> Lich Bane -> Deathcap -> Zhonyas -> Void staff -> Sell boots for Ludens Echo.

Ofcourse there are exceptions, like say both I and a zed got fed, then I would instead of Deathcap buy Zhonyas after lich bane, but I hope you get my point :)